A flaky titanium oxide particle has a shape relatively large in the ratio of a width and a length to a thickness thereof. For example, particles in which a thickness thereof is about 0.5 to 100 nm, and a width and a length are about 0.1 to 500 μm are known. Furthermore, there are flaky titanium oxide particles a thickness of which is made thinner to 10 nm or less and still thinner from 0.5 to 1 nm. Such a flaky titanium oxide particle is called a titanium oxide nanosheet. Such flaky titanium oxide particles are used in the same uses as known titanium oxide, for example, a white pigment, a photocatalyst, a catalyst, a catalyst carrier, an adsorbent and the like, a UV-ray shielding agent blended in sunscreen cosmetics, a paint, a film and the like, a filler for plastic, rubber and the like, a charge control agent for a toner and the like, a viscosity controlling agent for a paint, an ink and the like, an additive to a solid lubricant, a friction controller to a friction material, a synthesis material of fine ceramic or the like. In particular, when the titanium oxide nanosheet is used, a thin layer can be formed; accordingly, the titanium oxide nanosheet can be preferably used, by forming a titanium oxide film on a base material, as a photo-functional material such as a UV-ray shielding agent, a photocatalyst or a light reflection prevention agent. Furthermore, when titanium oxide nanosheets are blended in plastic, mechanical strength, heat resistance, a gas barrier property and the like can be improved.
As to an organic solvent dispersion obtained by dispersing flaky titanium oxide particles, JP 2006-206426A discloses that when a compound which forms organic cations, a titanium source and an organic solvent are mixed, an organic solvent dispersion of organic cation-containing layered titanate nanosheets can be obtained. Furthermore, JP 2005-220001A discloses a metal oxide thin film-forming coating solution in which a layered metal oxide is brought into contact with an alkyl amine or an alkyl ammonium compound having 6 or less carbon atoms in total in an organic polar solvent to expand an interlayer distance by intercalation, followed by adding a shearing force to cleave, and thereby metal oxide nanosheets having a thickness of 1 nm or less are formed.    Patent Document 1: JP 2006-206426A    Patent Document 2: JP 2005-220001A